The microphone technology in your smart speaker, it’s pretty impressive.
When you talk, sound leaves your mouth, but it doesn’t travel in a straight line. It travels like a shotgun and it just blasts in all different directions and then bounces around the room and you get reflections.
It’s called reverb, and those reflections are timed differently, depending on the size of the room and the materials in the room and how much of the sound gets absorbed vs reflected.
That’s why your voice sounds different in the bathroom.
And so, to understand what’s being said, a microphone needs to pick up the direct signal that comes straight from the mouth, plus the reflections that are generated in the room.
Most smart speakers have more than one microphone. Some of them have about eight microphones. And so you’ll need to do all of that processing x 8,
then combine those 8 signals into one signal to then actually do the processing.
But that’s not all.
Imagine you’re not stood right next to the speaker. Imagine you’re stood at the back end of the room. Couple that with the sound of a Hoover and a screaming child and you’ve got some pretty complex work to do
So next time Alexa doesn’t quite hear what you’re saying or Google Assistant doesn’t understand you, give it a break. It’s trying to do some pretty complex stuff.